3. Create a new database and migrate all the tables from the old one to the new one.

4. The Crazy Option

Shutdown the MYSQL Database
Locate the location where MYSQL save the databases. (ususally they are located in /var/lib/mysql/ on a Linux platfrom)
Rename All Old database Files to new Database filenames (something like mv olddb.* to Nename.*)
Restart The Database
Make sure you check the Grant permission.